RESUMO
OBJECTIVE: Middle cerebral artery (MCA) aneurysm is a common source of aneurysmal subarachnoid hemorrhage, but distal MCA aneurysms are rare. This present study was conducted to evaluate the clinical characteristics of the distal MCA aneurysms and the optimal treatment for a good outcome. METHODS: Among 3323 patients underwent aneurysmal surgery from 1975 to 2007, 21 patients with distal MCA aneurysm was identified. The clinical, radiological and operative records of 21 patients with distal MCA aneurysms who underwent surgical management were reviewed retrospectively. The clinical outcomes were evaluated according to the Glasgow Outcome Scale. RESULTS: The clinical analyses of 21 patients with distal MCA aneurysms has following characteristics. (1) Mean aneurysm size of 5.3mm (range 2~8mm). (2) All lesions were considered to be saccular except one case. (3) The location being M2 in one patient, M2-3 junction in 12, M3 in 3, and M4 in 5 patients. (4) In 7 of 21 patients, initial CT scan revealed intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH). (5) All patients underwent surgical treatment for aneurysm; the procedures were clipping in 17 patients, trapping in 2 patients, trapping and end-to-end anastomosis in 1 patient, and direct vessel suture in 1 patient. (6) All patients without ICH had a good recovery. However, the patient with ICH had a different prognosis. Of the 7 patients with ICH, 4 patients had a good recovery and 2 patients had a moderate disability. 1 patient died due to severe brain swelling. CONCLUSION: The patients with distal MCA aneurysm were relatively young, and there was no female predominance. The aneurysms have high rates of cardiac problems such as infective endocarditis or mitral valve prolapse, attributing to be developed infectious aneurysm. Ruptured distal MCA aneurysms are rare and can cause life-threatening ICH with SAH. However, the appropriate surgical treatments can obtain a favorable outcome.